If it’s high performance, high RPM and high valve spring loads you would need the high-performance bearings,” says Bob McBroom, VP of engineering and manufacturing at Dura-Bond Bearing Company, Carson City, NV. “In a stock car engine you would run a standard babbitt bearing. One is a standard babbitt bearing, another is a high-performance bearing, and the third is an even higher-performance Teflon-coated bearing with some of the closest tolerances on the market.

You simply need to pay more attention to details when installing aluminum cam bearings and be certain to verify critical tolerances.Ĭam bearings are usually available in a range of basic bearing constructions. The benefits of aluminum cam bearings, however, far outweigh the compromises. The trade-off lies in the fact that aluminum alloy is harder than babbitt but is less forgiving with regard to contamination, cam bearing bore misalignment, and less-than-ideal lubrication. This specially developed alloy is much stronger than babbitt and can withstand much higher loads. In order to address higher loads and temperatures, babbitt, for the most part, has been replaced with an aluminum alloy.

These operating conditions sometimes result in fatigue or deformation of babbitt bearings. However, performance engines often operate at higher temperatures and feature higher valvetrain loads, which places babbitt material at a disadvantage. This soft material does an excellent job of being able to withstand particle contamination and less-than-ideal lubrication on initial engine startup. Babbitt is a soft, slippery material composed primarily of lead and tin. In previous years, the vast majority of cam bearings were manufactured with a babbitt lining.

Pontiac 350 cam selection